Charting Course: Life in the Universe

The National Academy of Science released this summer their pre-publication report (PDF) on astrobiology, entitled "Life in the Universe". The Space Studies Board highlighted the major findings so far. Excerpts show the exciting directions for next milestones.

Our Milky Way galaxy is packed with 400 billion stars and perhaps even more planets. "We are not looking for a grand vision. We are looking for the beginnings of vision." -John Baross, 2001, University of Washington, Co-chair. Committee on the Evolution and Origins of LifeCredit: NASA

Significant scientific advances have occurred in the past 5 years in addressing some of the questions identified in the astrobiology roadmap. A few example areas that have borne particular fruit, with example references include the following:

The mix of flight programs, which run from Discovery missions (e.g., Mars Pathfinder, Near-Earth Asteroid Rendezvous, and Stardust) through to flagship mission (e.g., Galileo and Cassini), provides a varied tapestry of flight-preparation times, risks, and rewards.

Notable among these has been the spectacular exploration of the outer solar system, commencing with the Pioneer missions, through the Voyager discoveries about the satellite systems of the giant planets, and culminating in the Galileo discoveries about Europa and the promise of Cassini discoveries at Saturn.

In a universe brimming with stars, it is difficult to imagine that life exists nowhere else. "The countless worlds in the universe are no worse and no less inhabited than our Earth." Thus the Italian philosopher-scientist Giordano Bruno articulated a vision for astrobiology (De L’infinito Universo e Mondi, 1584). Credit: NASA/STScI/ESA

Laboratory studies have blossomed as well, because techniques developed to analyze the Apollo lunar samples have been applied to the large numbers of meteorite samples found, serendipitously, through Antarctic exploration. Among these samples are pieces of Mars and the Moon, and laboratory studies inspired the goal of directly collecting small body samples that is being realized through the ongoing Stardust mission.

What’s Next

Perhaps most extraordinarily, the detection and now characterization of extrasolar planets has created a new intellectual realm within planetary science, and as well has produced profound synergies between observational planetary astronomy and its parental roots in large telescopic observations of the cosmos. Giant planets are being detected indirectly and, in a few cases, observed directly to allow analyses of their bulk and atmospheric properties. Flight opportunities range in scale from Explorer (microlensing) through Discovery (Kepler-transits) to flagship (Space Interferometry Mission) missions.

One cannot come away from the national astrobiology meetings without remarking how well the big questions are being addressed, how easy it is to explain to the informed layman what the research means, and the extent to which talented students are attracted to this research area.